I’m as frustrated as Craig: the majority of issues I’ve had with Yosemite are consistent with reported
discoveryd problems. It’s not just for Wi-Fi devices, because our wired computers have the same issues, and it’s not just with AirPort routers, because I don’t use one.
I had to disable Bonjour on my printer to work reliably with Yosemite, my AirPlay menu today includes “Apple TV (3)”, and just ten minutes ago, I had to put some files onto a NAS share first to give to my wife because her computer disappeared from Finder visibility and local DNS. I connect to my headless Mac Mini by IP address every time now because it’s almost never visible.
Your computer can’t see my computer on the network or vice versa? The only solution that works is to reboot everything, just like using Windows fifteen years ago. Before Yosemite, I never had these issues on Macs.
Yosemite is now 6 months old, these bugs still aren’t fixed, and it feels like they probably won’t be fixed anytime soon. Yosemite is probably in minimal-maintenance mode as primary resources have likely moved on to headlining features for 10.11. This is what’s so frustrating about today’s Apple: if a bug persists past the early beta stages of its introduction, it rarely ever gets fixed. They’re too busy working on the new to fix the old.